Pancreatic cancer (PC) is the most deadly cancer with an overall 5-year survival rate of ~7% over the last decade. This is primarily because PC tends to develop surreptitiously over the course of multiple decades (i.e., over 20 years from initiation to metastasis) with no appreciable symptoms presenting until the very final stages of cancer progression. There are no techniques available which are suitable for population- wide screening of PC. The goal of this project is to develop and test a novel optical technology for the detection of PC. This technology will target the ultrastructural alterations presenting in Field Effect of Carcinogenesis (FC). FC is the phenomenon by which a number of physical alterations in tissue structure occur throughout an entire affected organ at an early time- point, long before metastasis. These physical alterations happen at subdiffractional (nano) length-scales. Light scattering techniques have shown the ability to detect and characterize these ultrastructural alterations in both in-vivo and ex-vivo studies for multiple cancer types. The purpose of this project is to extend on previous work and develop a noninvasive fiber optic probe for use during an upper endoscopy procedure to probe the periampullary region of the duodenum for ultrastructural alterations. The periampullary region of the duodenum serves as a surrogate site from which cancer risk status can be assessed, since it is exposed to the same milieu as the pancreatic duct (pancreatic juices and microbiome) and the pancreatic duct is not practical for probing. The approach of this project will be divided into roughly two phases: 1) an engineering phase and 2) a clinical testing phase. First I will develop simulations to accurately model the probe design. I will build, test, and validate the probe design with phantoms. The probe will then be tested with human subjects to develop a prediction rule for detecting pancreatic cancer, and finally the prediction rule will be validate with an independent set of patients.